body {
    background: yellow;
}
/*记得写宽高。。*/
#qwe{
    background-image: url(../img/1.png);/*3.2k*/
    width: 200px;
    height: 50px;
}
#asd{
    background-image: url(../img/2.png);
    width: 200px;
    height: 50px;
}